Circulation controller



' CIRCULATION CONTROLLER Filed Dec. 5, 1938 2 Sheets-Sheet l ATTORNEYS.

June 17, 1941. w DILLON 2,245,967

CIRCULATION CONTROLLER Filed Dec. 5, 1958 2 Sheets-Sheet 2 Q Q *3 S\ INVENTOR.

ZZ/ezzdeZZ/ZULH M. BY 7W ATTORNEYS.

Patented June 17, 1941 UNITED STATES PATENT OFFICE 2,245,967 cmcumrron CONTROLLER Wendell M. Dillon, North Andover, Mass, assignor to Watts Regulator Company, Lawrence, Mass, a corporation of Massachusetts Application December 5, 1938, Serial No. 243,965

4 Claims.

My invention relates to a hot water system of the recirculating type together with a recirculating control valve for governing the temperature in the recirculating portion of the system.

Among the objects of my invention is the provision of a new and improved system of circulation control for liquids which is simple in its construction and eflicient in its operation.

Another object is the provision of a new and improved system including a circulation control device for maintaining a predetermined temperature condition in a recirculating hot water system during periods of no draft when no water is being drawn from the system.

Another object is the provision of a new and improved liquid circuit containing a circulation control valve device which is so constructed that it can completely shut ofi one opening thereto while still maintaining an open passage through it to allow free circulation of liquid at another temperature.

A further object is the provision of a new and improved system including a control valve provided with a plurality of outlets, one of which is adapted to be positively closed by a resiliently mounted valve subject to being opened by pressure exerted upon one side of the valve during periods of draft and to be opened or closed during periods of no draft by means of a thermal element. Included among the objects also is the provision of an adjusting means whereby the thermal element may be caused to actuate under difierent predetermined temperature conditions.

A further object still is the provision of a hot water supply system including a recirculating system or loop for hot water and a circulation control valve interposed in the loop so that the temperature of water therein during periods of no draft may be kept at a desirable amount, neither too hot nor too cold for the conditions to which it is adapted.

Another object is the provision of a new and improved hot water system featuring a recirculating system or loop of heated water connected to a heater either with or without a storage tank in which is incorporated a circulation control valve connected by means of a. by-pass across the recirculation loop in order to provide a constant predetermined temperature for water in the loop.

With these and other objects in view, my invention consists in the construction, arrangement and combination'of the various parts of my device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 is a longitudinal sectional view of the circulation control valve device embodying my invention. 4

Figure 2 is a horizontal sectional view of the control valve device taken on the line 2-2 of Figure 1.

Figure 3 is a right end elevation of the valve device.

Figure 4 is a left end elevation of the device shown partially in section taken on the line 4-4 of Figure 1.

Figure 5 shows a typical hot water system incorporating the circulation control valve device.

Figure 6 is a modified form of a hot water system including a boiler and heater showing a specific use for the control valve device.

In hot water systems and particularly hot water supply systems for domestic use wherein water is drawn therefrom at intermittent intervals difliculty has been experienced in the past in preserving a proper temperature for the water supply at points immediately adjacent the taps. For example, a system designed for supplying a certain limited number of taps which are being used more or less constantly during the day when water is being continuously drawn from the system will not always operate properly during and directly after late hours of the night when practically no water is drawn oil from the system.

In order to avoid difficulties it is frequently the practice to use what may be termed a tempering valve and a recirculating system or loop so that hot and cold water may be mixed in certain proportions to supply water to the service line at a suitable temperature for use and then recirculated back to some source such as a storage tank in order that there may be a continuous passage of water past the service outlets. Such a system, while working properly during periods of use fails to operate during periods of no use. Under such circumstances, which occur chiefly during the late hours of the night and early hours of the morning, tempering valves of the sort commonly used are not designed to completely shut off hot water from the tank and as a result the water in the recirculating system or loop gradually heats up to tank temperature sufliciently so that the first users of the water in the morning are apt to be scalded by the first water drawn off. In such systems which do not even employ a tempering valve these conditions of excessive but water at the taps in the morning is especially pronounced.

To avoid dlfilculties of the type referred to, my invention contemplates the provision of a circulation controlling valve device inserted in the recirculating system or loop and provided with a by-pass connection so that in eflfect'there is formed another recirculating loop within the first. This installation is best seen in Figure as applied to an ordinary hookup for a domestic hot water system. In a system of the sort shown,

7 hot water-is circulated from the tank to outlet pipes and then back again to the tank but in the system there is provided a by-pass to the circulation control valve device so that when no water is being drawn from the system a larger percentage of the recirculation will take place only in the loop adjacent the'outlets with-the circulation control valve device admitting periodically only enough hot water from the tank to compensate for natural heat losses in the loop.

As will be observed in Figure 1 water may circulate constantly through the two oppositely disposed openings of the control valve device but can be positively shut oil from the single lateral opening, although by reason of a flexible mounting for the valve if the pressure is reduced in the loop which freely circulates water through the valve device, then the valve may be lifted from the lateral opening due to water pressure behind it, permitting a required flow of water through the valve.

My invention comprises essentially a circulation control valve device including a valve body indicated generally by the numeral III which has formed therein a rather ample space I2 in which there is an inlet opening I4 at the bottom, an outlet opening I6 at the top and a supply opening I8 at one side. On the side of the body opposite from the supply opening there is a large rectangular opening 20 closed by a cap or cover plate 22 which is fastened to the body by means of screws 24 making a fluid tight joint therewith. At the inlet opening I4 there is shown the end 26 of a bypass line, at the outlet opening I6 is shown the end 28 of a service line and at the opening I8 is shown the-end 30 of a tempered or heated water supply line. Recirculating water is designed to pass from the bypass line 26 through the valve and outward through the service line 28 while tempered or heated water is designed to pass into the valve from the tempered water line 3|] mixing within the space I2 with the recirculating water and then pass together with it outward through the service line 28.

The supply opening I8 is provided with a valve seat 32 within the valve body upon which is.

seated a disc valve 34. The disc valve is held in place by means of a spiral coil of bi-metal 36 which is attached by means of a bolt or rivet 38 to the center of the disc valve 34. At its opposite or inner end the spiral coil of bi-metal is attached to a sleeve 48 which is designed to rotate about a pin 42. This pin in turn is mounted upon a U- shaped bracket 44 which suspends it in place approximately at the center of the upper portion of the space I2. The U-shaped bracket in turn is secured by means of screws 46'to the cap 20 so that upon removal of the cap the entire bimetallic element and disc valve can be extracted from the valve body.

In order to vary the temperature at which the bimetallic element becomes efiective, there is provided an adjusting device comprising a lever 48, one end of which is attached to the sleeve 40,

the other end of which is extended adjacent the cap 28. The other end thus extended has a portion 50 bent to an L-shape so as to lie parallel to the cap and in this portion there is provided an aperture 82 wh'lchin the embodiment shown is in the form oi a slot. Located in the cap 28 adjacent the portion is an adjusting screw 54 which extends through the cap and is provided with a screw driver slot 58 accessible from outside the valve. The inside end of the adjusting screw is provided with a flange 58 bearing against a washer at the inside wall of the cap from which protrudes an eccentric pin 68 which is positioned within the aperture 52 of the lever 48. A lock nut 62 is provided to fix the position of the screw 54.

When operating the adjustment the lock nut 62 is loosened and the adjusting screw 54 rotated in one direction or another, whereupon by means of the eccentric projection 68 the lever 48 is tilted upward or downward. thereby decreasing or increasing tension on the bimetallic coil as the case may be. This change in tension correspondingly changes the temperature at which the coil will permit opening and closing of the disc valve 34.

A hot water system in which the valve is used is shown in Figure 5 and comprises a heater 10 connected to a storage tank 12 by means of a supply pipe line I4 and a return pipe line 16. The storage tank in turn is supplied by a water main 18 which introduces water, which usually is relatively cold, into-the storage tank through the pipe 19. Water is drawn from the tank through a pipe line 80 to a tempering valve 82 which mixes storage tank water with cold water from the main, discharging it through a tempered water line 30 to the circulation controlling valve In to which it is connected at the supply opening I8. From the circulation controlling valve device I0, tempered water is conducted through the service line 28 to a series of service outlets 84, 86 and 88 which are customarily supplied with taps, not shown. From the service outlets water is conducted through a return pipe line 90 past a check valve 82 into the bottom of the storage tank.

The bypass line 26 is connected between the return line 80 and the circulation controlling valve device in order to complete a recirculating loop outside the storage tank so that water may circulate from the circulation controlling valve device III through the pipe system including the service outlets and back again to the circulation controlling valve device without passing through the storage tank. An arrangement of this sort has the effect of producing two circulating loops, one within the other, one including the tank, tempering valve, service line and return line, and the other comprising only the service line, bypass line and a portion of the control valve device through which water continuously circulates.

Operation Figures 5 and 6 show adaptations of the circulation control valve device to recirculating systems. In Figure 5, for example, there is shown a boiler I38 which is connected by means of pipes I32 and I34 to a heater I36. The heater in turn is connected by means ofa supply line I38 to the circulation control valve I 8 from which water emerges flowing through a service line I40 to a storage tank I42. Return water from the storage tank flows through a return line I44 back to the heater and a bypass line I46 is connected from the return line to the circulation control valve. An additional pipe line I48 is connected to suitable service, outlets not shown and cold water is supplied through the pipe I50. In a system of this sort the circulation controlling valve by being positioned directly adjacent the heater serves to maintain a constant temperature for water in the storage tank I42 and thereby indirectly serves to maintain a desired temperature in the circulation loop identified by the pipe lines I48 and I50, the circulation controlling valve of course operating in the same manner as previously described.

In this embodiment the heating medium is the hot water supplied by the boiler which continually circulates through a loop formed by the boiler I30, pipes I32 and I34 and coils of pipe in the heater I36 at temperatures ranging from 180 to 212 F. Coils heated in this manner serve as a heat exchanger to transfer heat to water in the recirculating loop.

In some localities a great deal of lime is found in the water which causes trouble by precipitating out at high temperatures and depositing on the inside of hot water coils. To avoid trouble of this sort an arrangement such as shown in Figure 6 may be employed. In this system the circulation control valve device is designed to control the temperature of water entering the heater. As shown there is a boiler I52 which is connected by means of a supply line I55 to the control valve it which is connected by means of a service line I55 to a heater I58. From the heater a return line ISO is connected again to the boiler forming a loop and a by-pass line IE2 is connected between the return line I60 and the circulation control valve Ill. Hot boiler water is thereby caused to circulate through coils of pipe in the heater at a temperature controlled by the control valve device. The heater in turn is connected by the customary piping I54 to a storage tank I56 from which a return line I 58 conducts water back to the heater. The supply tank is served by a water main I18 and a service pipe line I12 is provided to draw hot water from a storage tank.

In a setup thus shown by Figure 6 the circulation control valve is designed to control the temperature of water flowing from the boiler to the heater. By properly setting the control valve the temperature of boiler water in the heating coils may be kept below the critical temperature at which lime and scale will deposit and will greatly promote long life and efliciency in the system. In so limiting the temperature, however, the boiler water is still maintained at a temperature in the neighborhood of 140 to 150 F. which is suficient to properly heat the water in the storage tank, which continues uninterruptedly circulating past the coils of hot water in the heater. Due, however, to the presence of the control valve water in the service line will always remain heated but will never be overheated.

There has thus been described a circulation control valve device of a distinctly novel structure which is capable of maintaining circulation of Water therethrough while at the same time selectively admitting or denying passage thereinto of water of another temperature adapted to modify the temperature of the water normally circulating therethrough. Such a device, as has been described, is suitable for a variety of uses by means of which it may maintain any selected temperature in a recirculating loop.

It is furthermore to be borne in mind that although the invention has been described priwherein it is desired to maintain a minimum high temperature, the valve may as readily be applied to cold water systems by a suitable reversal of the bimetallic element in order that the temperature in what may be termed a recirculating cold water loop might be prevented from passing above a certain temperature as for example brine pipes which might be used to cool a tank of water or for any generally cooling purpose.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of struc; ture or use of mechanical equivalents which may be reasonably included within their scope.

marily in connection with hot water systems,

I claim as my invention:

1. In a system for supplying liquid irom a main to a service outlet means at a preselected temperature, the combination of a first re-circulating loop including means for maintaining liquid at a portion thereof at an elevated temperature condition, a second recirculation loop connected with the service outlet means arranged in heat exchange relation with the first loop, one of said loops being adapted to continuously recirculate liquid through said one loop having an elevated temperature condition, a bypassing conduit in the other of said loops and a circulation control valve connected in said other loop adapted to control the bypassing of liquid therein for controlling the temperature of liquid supplied to the service outlet means.

2. In a hot water system for operation with a service line system, the combination of a water main for supplying fresh water, a source of heated waterincluding a heating device, a tank for heated water, pipe lines between the heating device and the tank comprising a circulating system, a circulation controlling valve device in said circulating system comprising a free passage therethrough for circulating water, a valved passage communicating therewith connected by a water line to said source and a valve for. said last passage having one position completely closing the hot water line and a plurality of progressively open positions, a thermal element in the path of circulating water operatively connected to said valve and adapted thereby to limit the admission of quantities of additional hot water to the circulating system. a

3. In a temperature controlled water system for operation with a service line system, the combination of a main-for supplying water thereto, a source of water at one predetermined temperature including a device for maintaining said temperature, a tank for the water, pipe lines between said device and the tank comprising a circulating system, a circulation controlling valve device in said circulating system comprising a free passage therethrough for circulating water, a valved passage communicating therewith connected by a water line to said source and a valve for said last passage having one position completely closing the water line from said source and a plurality of progressively open positions, a thermal element in the path of circulating water operatively connected to said valve and adapted thereby to limit the admission of quantities of additional water of a predetermined temperature to the circulating system.

4. In a hot water system for operation with a supply main and a service outlet means, the combination of a first circulating loop including a source of water having a relatively high temperature, a heat exchange device, a fluid passage connecting said source with said device and a return passage, a circulation control valve device including an opening connected directly to the source of hot water, a valve for opening and closing said opening, a constantly open passage adapted to communicate with the opening, a temperature responsive element in the passage attached to the valve to move said valve in re- 10 sponse to temperature conditions in said passage. and passage means from said constantly open passage to the heat exchanger and return, and a second circulating loop in heat exchange relation to the first loop connected with the service outlet means and adapted to continuously circulate water past the heat exchanger to supply said service outlet means at all times with water at a predetermined temperature.

' WENDELL M. DILLON. 

